U.S. patent number 7,187,549 [Application Number 10/882,433] was granted by the patent office on 2007-03-06 for heat exchange apparatus with parallel flow.
This patent grant is currently assigned to Teradyne, Inc.. Invention is credited to Tarzen Kwok, Nicholas J. Teneketges.
United States Patent |
7,187,549 |
Teneketges , et al. |
March 6, 2007 |
Heat exchange apparatus with parallel flow
Abstract
In at least one embodiment, the present invention is a heat
exchange apparatus which includes at least one heat exchanger, an
intake manifold, and at least one multichip module. Where the
intake manifold is in fluid communication with each heat exchanger
and where the intake manifold is capable of providing the heat
exchange medium separately to each heat exchanger. Where the each
multichip module is positioned at least adjacent to at least one
heat exchanger, such that heat can transfer between each multichip
module and at least one heat exchanger.
Inventors: |
Teneketges; Nicholas J.
(Thousand Oaks, CA), Kwok; Tarzen (Thousand Oaks, CA) |
Assignee: |
Teradyne, Inc. (Boston,
MA)
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Family
ID: |
35385364 |
Appl.
No.: |
10/882,433 |
Filed: |
June 30, 2004 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20060002086 A1 |
Jan 5, 2006 |
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Current U.S.
Class: |
361/699;
165/104.33; 165/80.4; 174/15.1; 257/714; 257/E23.098; 361/689 |
Current CPC
Class: |
H01L
23/473 (20130101); H01L 2924/0002 (20130101); H01L
2924/0002 (20130101); H01L 2924/00 (20130101) |
Current International
Class: |
H05K
7/20 (20060101) |
Field of
Search: |
;361/687-690,698,699,711,719,721 ;257/714,716 ;174/15.1
;165/80.3,104.33 ;62/259.2 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1 491 570 |
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Nov 1977 |
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GB |
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1 517 650 |
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Jul 1978 |
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GB |
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Other References
IBM Technical Disclosure Bulletin vol. 21, No. 8 Jan. 1979, pp.
3378-3380. cited by examiner .
IBM Technical Disclosure Bulletin vol. 25, No. 9 Feb. 1983, p.
4517. cited by examiner .
IBM Technical Disclosure Bulletin vol. 30, No. 5 Oct. 1987, p. 413.
cited by examiner.
|
Primary Examiner: Chervinsky; Boris
Attorney, Agent or Firm: Aagaard, Esq.; Eric J. Balzan,
Esq.; Christopher R.
Claims
What is claimed is:
1. A heat exchange apparatus comprising: a) at least one heat
exchanger; b) an intake manifold in fluid communication with each
heat exchanger of the at least one heat exchanger, wherein the
intake manifold is capable of providing a heat exchange medium
separately to each heat exchanger; c) an exhaust manifold adjacent
to the intake manifold, the exhaust manifold being in fluid
communication with each heat exchanger of the at least one heat
exchanger, wherein the exhaust manifold is capable of receiving the
heat exchange medium from each heat exchanger; d) a plurality of
multichip modules mounted to a card, wherein each multichip module
of the plurality of multichip modules is positioned between a heat
exchanger and the card, such that heat can transfer between each
multichip module and a respective heat exchanger; e) the exhaust
manifold and the intake manifold positioned above and adjacent to a
side of the card; and f) the plurality of multichip modules being
mounted on the side of the card in a position lateral to the intake
manifold and the exhaust manifold.
2. The heat exchange apparatus of claim 1, wherein the intake
manifold is capable of providing the heat exchange medium
substantially equally to each heat exchanger.
3. The heat exchange apparatus of claim 1, wherein each multichip
module abuts at least one heat exchanger.
4. The heat exchange apparatus of claim 3, wherein each multichip
module is mounted to at least one heat exchanger.
5. The heat exchange apparatus of claim 3, wherein each multichip
module is compression mounted to at least one heat exchanger.
6. The heat exchange apparatus of claim 3, wherein each multichip
module further comprises a pin electronics die, and wherein the pin
electronics die abuts at least one heat exchanger.
7. The heat exchange apparatus of claim 1, wherein each heat
exchanger is a cold plate.
8. The heat exchange apparatus of claim 1, wherein the heat
exchange medium is a liquid.
9. The heat exchange apparatus of claim 4, wherein the heat
exchange medium is an inert liquid.
10. The heat exchange apparatus of claim 1, further comprising at
least one first connector, wherein each first connector of the at
least one first connector, is positioned between the intake
manifold and each heat exchanger, such that each heat exchanger can
be disconnected from the intake manifold.
11. The heat exchange apparatus of claim 1, further comprising at
least one first connector, wherein each first connector of the at
least one first connector, is positioned between the intake
manifold and each heat exchanger, further comprising at least one
second connector, wherein each second connector of the at least one
second connector, is positioned between the exhaust manifold and
each heat exchanger, such that each heat exchanger can be
disconnected from the intake manifold and the exhaust manifold.
12. The heat exchange apparatus of claim 11, wherein each first
connector comprises a quick-release connector, and wherein each
second connector comprises a quick-release connector.
13. The heat exchange apparatus of claim 11, wherein each first
connector comprises at least one valve for controlling the flow of
the heat exchange medium, and wherein each second connector
comprises at least one valve for controlling the flow of the heat
exchange medium.
14. The heat exchange apparatus of claim 11, further comprising a
combined manifold structure comprising the intake manifold and the
exhaust manifold.
15. The heat exchange apparatus of claim 6, wherein the pin
electronics die is positioned to be cooled by the heat exchange
medium prior to cooling other die within the multichip module.
16. In automated test equipment having a printed circuit board, a
plurality of multichip modules mounted to the printed circuit
board, a coolant source for providing a liquid coolant, a coolant
receptor for receiving a liquid coolant, and a liquid cooling
apparatus in fluid communication with the coolant source and the
coolant receptor, the liquid cooling apparatus comprising: a) a
plurality of cold plates, wherein each cold plate of the plurality
of cold plates abuts a multichip module of the plurality of
multichip modules, each mulitichip module being positioned between
the printed circuit board and the abutting cold plate, such that
heat is capable of transferring between the multichip module and
the abutting cold plate; b) an intake manifold positioned above and
adjacent to a side of the printed circuit board, wherein the intake
manifold is in fluid communication with each cold plate in a
parallel configuration, such that the intake manifold is capable of
providing coolant to each cold plate separately; c) an exhaust
manifold positioned above and adjacent to a side of the printed
circuit board, wherein the exhaust manifold is in direct fluid
communication with each cold plate in a parallel configuration,
such that the exhaust manifold is capable of receiving coolant from
each cold plate separately; and d) the plurality of multichip
modules being positioned lateral to and along a common side of the
exhaust manifold, and wherein the plurality of multichip modules
are positioned lateral to and along a common side of the intake
manifold.
17. The liquid cooling apparatus of claim 16, further comprising:
a) an intake connector mounted between the coolant source and the
intake manifold, wherein the intake connector is capable of
separating a fluid connection between the intake manifold and the
coolant source, such that the liquid cooling apparatus is separable
from the coolant source; and b) an exhaust connector mounted
between the exhaust manifold and the coolant receptor, wherein the
exhaust connector is capable of separating a fluid connection
between the exhaust manifold and the coolant receptor, such that
the liquid cooling apparatus is separable from the coolant
source.
18. The liquid cooling apparatus of claim 17, wherein the intake
connector comprises a quick-release connector, and wherein the
exhaust connector comprises a quick-release connector.
19. The liquid cooling apparatus of claim 16, wherein the intake
manifold and the exhaust manifold are mounted to the printed
circuit board.
20. The liquid cooling apparatus of claim 19, further comprising a
combined manifold structure comprising the intake manifold and the
exhaust manifold.
21. The liquid cooling apparatus of claim 17, further comprising a
plurality of inlet cold plate connectors, wherein each inlet cold
plate connector of the plurality of inlet cold plate connectors, is
positioned between the intake manifold and a cold plate of the
plurality of cold plates, a plurality of outlet cold plate
connectors, wherein each outlet cold plate connector of the
plurality of outlet cold plate connectors, is positioned between
the exhaust manifold and a cold plate of the plurality of cold
plates, such that each cold plate can be disconnected from the
intake manifold and the exhaust manifold.
22. The liquid cooling apparatus of claim 21, wherein each inlet
cold plate connector comprises a quick-release connector, and
wherein each outlet cold plate connector comprises a quick-release
connector.
23. The liquid cooling apparatus of claim 16, wherein each
multichip module further comprises a pin electronics die, and
wherein each pin electronics die abuts at least one cold plate.
24. The liquid cooling apparatus of claim 23, wherein each pin
electronics die abuts at least one cold plate with a thermal paste
therebetween.
25. The liquid cooling apparatus of claim 16, wherein the multichip
module comprises at least one pin electronics chip positioned
within the multichip module such that the at least one pin
electronics chip is cooled prior to cooling other chips within the
multichip module.
Description
BACKGROUND
Automated test equipment, or ATE, provides semiconductor
manufacturers the capability of individually testing each and every
semiconductor device fabricated during production. The testing is
usually carried out at both the wafer level and the packaged-device
level to ensure operability of the devices before reaching the
marketplace.
Modern semiconductor devices typically have anywhere from
thirty-two to over one-thousand pins, generally requiring a
corresponding number of channels in the semiconductor tester to
thoroughly verify the operation of the device. Each channel usually
comprises a signal path including the necessary pin electronics for
sending and/or receiving test signals to and from a pin on the DUT.
In conventional testers, to maximize component density and minimize
the size of the tester, the channels are often formed on printed
circuit boards resident within a testhead. The testhead is
separated from the main body of the tester for coupling to the DUTs
that are mounted on a prober or handler.
Because of the relatively high concentration of circuit boards
within a conventional testhead, specialized cooling systems are
generally employed to maintain a stable thermal environment. Some
prior systems have employed air cooling, which typically includes
elaborate ducting that takes up valuable space within the testhead.
As a result, these air cooling systems contribute to a larger
overall footprint for the tester. Moreover, because the airflow
must overcome the resistive effects of ducting, nozzles and the
uneven shapes and surfaces of the boards, the air cooled systems
tend to not be as efficient as desired.
Other approaches have included liquid cooling systems that
circulate a fluid, typically water, from a liquid cooler, i.e. a
refrigeration unit, and past the heat producing electronic
components, i.e. microchips, and back to the cooler. Liquid is
passed through cooling blocks, which are attached to the electronic
components, to allow the heat to transfer from the components to
the liquid. In these systems, the cooling blocks are attached to
one another with tubes or hoses, in series to form a single path or
channel for the liquid to pass though. That is, these systems flow
the liquid from the cooling unit, which typically includes a pump,
to a first cooling block, where heat is transferred from the
electronic component, which the cooling block is mounted on, into
the liquid. Then the liquid leaves the first cooling block through
a connecting tube to a second cooling block, where heat is again
transferred into the liquid from another electronic component. The
liquid continues to move through a series of cooling blocks in
succession, having heat transferred into it at each cooling block,
until it returns to the cooling unit.
Because the liquid is heated each time it passes through a cooling
block, the temperature varies unpredictably with each cooling block
in the series of cooling blocks. That is, with such cooling systems
each electronic component will be operating at a different
temperature, with the temperature rising along the path of the
liquid through the cooling blocks.
Lately, the trend has been with modern electronic components,
especially those used in current automated test equipment, of
becoming more and more sensitive to temperature levels, and any
fluctuations thereof. To optimize performance of these components
and to obtain uniform performance with among a set of components, a
stable and common temperature level is desired across all the
components. This is difficult to achieve with the variable liquid
temperatures provided by the prior liquid cooling systems.
Therefore, a need exists for a cooling system that provides an
uniform, predictable and consistent cooling environment for each of
the electronic components being cooled. Such a system should allow
for ease of access to reduce the time needed for servicing and, as
a result, minimize overall equipment downtime.
SUMMARY
In at least one embodiment, the present invention is a heat
exchange apparatus which includes at least one heat exchanger, an
intake manifold, and at least one multichip module. Where the
intake manifold is in fluid communication with each heat exchanger
and where the intake manifold is capable of providing the heat
exchange medium separately to each heat exchanger. Further, each
multichip module is positioned at least adjacent to at least one
heat exchanger, such that heat can transfer between each multichip
module and at least one heat exchanger.
The heat exchange apparatus can also include an exhaust manifold.
The exhaust manifold is in fluid communication with each heat
exchanger and is capable of receiving the heat exchange medium from
each of the heat exchangers. Also, the intake manifold can be
capable of providing the heat exchange medium substantially equally
to each heat exchanger.
Each multichip module can abut, be mounted to, and/or be
compression mounted to at least one heat exchanger. Each multichip
module can include a pin electronics die which itself abuts at
least one heat exchanger.
The heat exchangers can be cold plates or other similar structures.
The heat exchange medium can be a liquid and/or an inert liquid.
The heat exchanger system can also include at least one first
connector. Where each first connector is positioned between the
intake manifold and each heat exchanger, such that each heat
exchanger can be disconnected from the intake manifold. Likewise,
the heat exchanger system can include at least one second
connector. Where each second connector is positioned between the
exhaust manifold and each heat exchanger, such that each heat
exchanger can be disconnected from the exhaust manifold.
In another embodiment, the invention is in a piece of automated
test equipment having a printed circuit board, a plurality of
multichip modules mounted to the printed circuit board, a coolant
source for providing a liquid coolant, a coolant receptor for
receiving a liquid coolant, and a liquid cooling apparatus. The
liquid cooling apparatus is in fluid communication with the coolant
source and the coolant receptor. The liquid cooling apparatus
includes: a plurality of cold plates, wherein each cold plate abuts
a multichip module, such that heat is capable of transferring
between each multichip module and its abutting cold plate; an
intake manifold positioned at least adjacent to the printed circuit
board, wherein the intake manifold is in fluid communication with
each cold plate in a parallel configuration, such that the intake
manifold is capable of providing coolant to each cold plate
separately; and an exhaust manifold positioned at least adjacent to
the printed circuit board, wherein the exhaust manifold is in
direct fluid communication with each cold plate in a parallel
configuration, such that the exhaust manifold is capable of
receiving coolant from each cold plate separately.
The liquid cooling apparatus can also include an intake connector
mounted between the coolant source and the intake manifold, wherein
the intake connector is capable of separating a fluid connection
between the intake manifold and the coolant source, such that the
liquid cooling apparatus is separable from the coolant source and
an exhaust connector mounted between the exhaust manifold and the
coolant receptor, wherein the exhaust connector is capable of
separating a fluid connection between the exhaust manifold and the
coolant receptor, such that the liquid cooling apparatus is
separable from the coolant source.
In another embodiment of the present invention, a heat exchange
device includes a printed circuit board, a multichip module mounted
on the printed circuit board, a cold plate positioned on the
multichip module, and a fastener connecting the printed circuit
board and the cold plate. Where the fastener urges the cold plate
against the multichip module and the multichip module against the
printed circuit board. The cold plate can be positioned to form a
lid to the multichip module. The cold plate can also be a
compression plate.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of the present invention will be better
understood with regard to the following description, appended
claims, and accompanying drawings where:
FIG. 1 shows a top cut-away view of a parallel heat exchange system
in accordance with at least one embodiment of the present
invention.
FIG. 2 shows a top cut-away view of a portion of a heat exchange
system in accordance with at least one embodiment of the present
invention.
FIG. 3 shows a side view of a portion of a heat exchange system in
accordance with at least one embodiment of the present
invention.
FIG. 4a shows a top cut-away view of a heat exchange system in
accordance with at least one embodiment of the present
invention.
FIG. 4b shows a side cut-away view of a portion of a heat exchange
system in accordance with at least one embodiment of the present
invention.
DESCRIPTION
The present invention includes a heat exchange system which
functions to provide an even distribution of the heat exchange
medium across each of the heat exchangers. This distribution can
include providing even pressures, flow rates as well as
temperatures and composition of the medium. This distribution
allows the flows of the medium to be predictable and consistent
through each of heat exchangers. In turn, an even heat exchange
capacity, i.e. heat transfer rate, over each of the heat exchangers
is achieved. As such, the temperatures of each of the heat
exchangers, and therefore the electronic components attached
thereto, can be kept at the same temperature, or within a
relatively narrow range of temperatures.
The even distribution of the heat exchange medium is achieved in
part with use of an intake manifold and an exhaust manifold. By
having each of heat exchangers attached to a single common supply
of the heat exchange medium, the distribution to each heat
exchanger can be kept even.
The ability of the parallel heat exchange system to keep the heat
transfer, and thus the temperature, the same across all of the heat
exchanges and their associated electronic components, is in direct
contrast to the serial cooling systems, described above. Because a
serial system flows coolant through one cooling block after
another, in succession, the conditions, i.e. temperature, of the
coolant will be altered after passing through each cooling block.
As a result, the temperatures across the cooling blocks vary along
the path of the flow of the coolant.
In temperature sensitive applications, such as cooling of
electronic components, i.e. chip modules, the heat exchange systems
must be capable of maintaining relative constant temperatures on
each component. Failure to do so can result in dramatic reductions,
or errors, in performance, and/or damage to the components. More
specifically, adverse temperatures can affect timing signals of
chips, and, due to increased electrical resistance, certain analog
functions, as well as increased noise.
On the other hand, predictability in cooling allows for more
efficient component designs, thereby increasing performance and
lowering costs. With narrower operating temperature ranges,
components can be designed to operate at higher frequencies and to
use less power.
With multichip modules, or MCMs, used in automated test equipment,
or ATE, sensitive pin electronics die used within the MCM typically
can not meet their performance specifications without tightly
controlling their operating temperatures. In some embodiments of
the present invention, the temperature range of the MCMs have been
found to be able of being maintained within a .+-.1.degree. C.
temperature range.
FIG. 1 shows a top view cut-away of a parallel heat exchange system
in accordance with at least one embodiment of the present
invention. As shown, a heat exchange or cooling system 100 is
positioned on a printed circuit board or card 160, such that it is
capable of cooling each of the components or devices 170. By being
arranged to supply cooling to each of the devices in a parallel
arrangement, the heat exchange system 100 is capable of maintaining
the temperature of each device at the same, or at least
substantially the same, temperature. That is, all the devices can
be keep in a relatively narrow common range of temperatures. This
can result in improved and more uniform performance and provide a
more common life span of each device, reducing the overall amount
of servicing required.
The cooling system 100 includes an inlet or intake manifold 110,
inlet or intake tubes or hoses 120, heat exchangers 130, outlet or
exhaust tubes or hoses 140 and an outlet or exhaust manifold 150.
The card 160 includes an edge 162. The devices 170 are mounted on
the card 160 adjacent the edge 162. The flow directions of the heat
exchange medium (not shown), in this embodiment, are shown
generally by the arrows A1, A2, A3, A4, A5 and A6.
The intake manifold 110 functions to allow an incoming flow of the
heat exchange medium to be evenly distributed over a set of tubing
connected to the manifold 110. The intake manifold 110 includes a
common or distribution region 112, openings 114, and an open end
116. The general flow direction of the heat exchange medium through
the intake manifold 110 is shown by the arrow A2.
Depending on the embodiment, the intake manifold 110 can be mounted
on the card 160, positioned over the card 160, or positioned
adjacent to the card 160. With the intake manifold 110 mounted on
to the card 160 it allows the heat exchange system 100 and the card
160 to be a single unit, making installation, removal and servicing
of the combined unit easier and quicker. Which in turn can reduce
the time and cost of maintenance and repair.
The heat exchange medium used in the present invention can be any
of a variety of substances including a liquid or a gas. Usable
liquids include inert fluids and other fluids, such as water,
flourinert dielectric fluid, HFE and FC77 both available from 3M
corp. of St. Paul, Minn. Usable gases include air, helium, as well
as other gases. In the embodiment shown in FIG. 1 an inert fluid
can be used as the heat exchange medium.
The distribution region 112 receives the heat exchange medium from
an external source (not shown), such as a cooling system, a
refrigeration unit, a heat exchanger, a heater, pump, reservoir or
the like. As the medium moves into the distribution region 112, it
is applied evenly to each of the openings 114. The specific size
and shape of the distribution region 112 can vary and depending on
factors including the flow rates into and out of the distribution
region 112, and the properties of the heat exchange medium, i.e.
pressure, compressibility, viscosity, and the like. In some
embodiments, as shown, the distribution region 112 is significantly
larger in cross-section than the openings 114 and the opening of
the open end 116. This allows the flow rate of the heat exchange
medium to reduce upon entering the distribution region 112 and
facilitates even distribution to the openings 114.
The openings 114 are positioned along the intake manifold 110 and
function to allow flow to be directed into each of the intake tubes
120 attached thereto. While shown being positioned along a common
side of intake manifold 110, in other embodiments the openings 114
can be on other sides, or about the manifold 110. While the size
and shape of the openings 114 can vary, to achieve a balanced and
even flow through each of the openings, the openings 114 typically
have a common size and shape. The particular size and shape of the
openings 114 is dependent on the particular application and can
vary depending on factors including the desired flow rate through
the openings 114, and the properties of the heat exchange medium,
as noted above.
The intake manifold 110 also includes the open end 116, which has
an opening 117, allowing the flow of heat exchange medium into the
manifold 110 from an external source (not shown). The external
source can be a coolant source. The size and shape of the opening
117 can vary depending on the embodiment, and on factors including
the flow rate and the properties of the heat exchange medium. The
open end 116 can also include a connector or intake connector 118,
which functions to attach the tube or hose from the external source
to the intake manifold 110. The connector 118 can include a valve,
or valves, to prevent or limit any leakage of the heat exchange
medium. The connector 118 can also be positioned away from the open
end 116 along the tube from the external source. The connector 118
can be a quick-disconnect connector to allow the external source
tube to be relatively quickly disconnected from the manifold 110.
Such a quick-disconnect connector facilitates the quick removal of
the card 160 from a test head, or any similar apparatus. This in
turn allows for reduced service time and less equipment down time.
Also, this provides more flexibility in allowing individual cards
to be serviced without impacting other cards in the equipment.
The intake tubes 120 are connected between the intake manifold 110
and the heat exchangers 130, and function to carry the heat
exchange medium therebetween. Each intake tube 120 includes an
inlet 122 and an outlet 126. The general flow direction is shown by
the arrow A3. The intake tubes 120 can be of any of a variety of
different materials including rubber, stainless steel, aluminum,
plastic, vinyl, and copper. The intake tubes 120 can be compliant
and/or flexible tubing which may be required for adjusting the
alignment of the any connectors placed along the intake tubes 120,
as described below.
The size and shape of the intake tubes 120 can vary depending on
the particular application. Factors including the desired flow rate
and the properties of the heat exchange medium determining the size
and shape used for the intake tubes 120. The outlet 126 is shown
being attached to the heat exchanger 130 along one of its sides,
however, the outlet 126 can be attached to heat exchanger 130 at
any of a variety of different points about the heat exchanger 130,
depending on the particular configuration of the inlet and outlet
of the heat exchanger 130.
Between the inlet 122 and the outlet 126, the intake tube 120 can
include a connector or first connector 124 which allows the intake
tube 120 to be separated into two portions on either side of the
connector 124. The connector 124 can include a valve, or valves, to
prevent or limit any leakage of the heat exchange medium. The
connector 124, along with a similar connector on the exhaust tubes
140, as detailed below, allows the heat exchanger 130 to be removed
from cooling system 100 without removing the rest of the cooling
system 100 from the card 160. As a result, the heat exchanger 130
may be removed to facilitate access to the device 170 or structure
being cooled by the heat exchanger 130, i.e. a MCM, as shown. This
allows individual components to be serviced without impacting other
components on the board. Also, with the heat exchanger 130 and the
device 170 being mounted to each other in an integrated unit, as
detailed below, the connector 124 facilitates the removal of the
unit from the channel card 160. The connector 124 can be a
quick-disconnect connector such as a QD connector available from
Eaton Aeroquip, Inc. located in Maumee, Ohio. The use of such a
quick-disconnect further reduces the time and effort need to
disconnect the tube. In turn, this further reduces the service time
and equipment down time. In some embodiments, the connector 124 is
referred to as an inlet cold plate connector.
The heat exchanger 130 functions to transfer heat between device it
is positioned with, i.e. mounted upon, and the heat exchange
medium. In some embodiments, as that shown, the heat exchanger 130
functions to cool the device 170 that is positioned under the heat
exchanger 130. In certain embodiments, the device 170 has the
coldplate bonded such that the cold plate is in close proximity to
components of the device, i.e. the bare or exposed dies in an MCM.
As noted above and as further detailed below, the heat exchanger
130 and the device 170 can be mounted together in an integrated
unit.
The size and shape of the heat exchanger 130 can vary depending on
the requirements of the particular application. For example, the
size of the heat exchanger can be directly dependent on the amount
of heat that must be transferred from the device it is mounted to,
and the device's surface area available for the heat transfer. The
heat exchanger 130 can be a cold plate with a variety of different
configurations, as further described below.
The heat exchanger 130 includes an inlet 132 and an outlet 134,
which depending on the configuration of the heat exchanger 130, can
be located at different positions about the heat exchanger 130.
The heat exchanger 130 can be of any of a variety of different
materials which aid in the heat transfer, including materials with
high heat transfer rates such as copper, brass, aluminum and the
like.
The exhaust tubes 140 are connected between the heat exchangers 130
and the exhaust manifold 150, and function to carry the heat
exchange medium therebetween. Each exhaust tube 140 includes an
inlet 142 and an outlet 146. The general flow direction is shown by
the arrow A4. The exhaust tubes 140 can be of any of a variety of
different materials including rubber, stainless steel, aluminum,
plastic, vinyl, copper. The exhaust tubes 140 can be compliant
and/or flexible tubing which may be required for adjusting the
alignment of the any connectors placed along the tubes 140, as
described below.
The size and shape of the exhaust tubes 140 can vary depending on
the particular application, with factors including the desired flow
rate and the properties of the heat exchange medium determining the
size and shape of the exhaust tubes 140. The inlet 142 is shown
being attached to the heat exchanger 130 along one of its sides,
however, the inlet 142 can be attached to heat exchanger 130 at any
of a variety of different points about the heat exchanger 130,
depending on the particular configuration of the inlet 132 and
outlet 134 of the heat exchanger 130.
Between the inlet 142 and the outlet 146, the exhaust tube 120 can
include a connector or second connector 144 which allows the
exhaust tube 120 to be separated into two portions on either side
of the connector 144. The connector 144 can include a valve, or
valves, to prevent or limit any leakage of the heat exchange
medium. The connector 144, along with the connector 124 on the
intake tube 120, allows the heat exchanger 130 to be removed from
cooling system 100, without removing the rest of the cooling system
100 from the card 160. As a result, the heat exchanger 130 may be
removed to facilitate access to the device 170 or structure being
cooled, i.e. the MCM, as shown. Also, with the heat exchanger 130
and the device 170 being mounted to each other in an integrated
unit, as detailed below, the connector 144 facilitates the removal
of the unit from the card 160. The connector 144 can be a
quick-disconnect connector such as a QD connector available from
Eaton Aeroquip, Inc. located in Maumee, Ohio. The use of such a
quick-disconnect further reduces the time and effort need to
disconnect the tube. In turn, this further reduces the service time
and equipment down time. In some embodiments, the connector 144 is
referred to as an inlet cold plate connector.
The exhaust manifold 150 functions to collect an outgoing flow of
the heat exchange medium from the exhaust tubes 140 to be sent out
of the system 100. The heat exchange medium can be sent to a
coolant receptor. The exhaust manifold 150 includes a common or
collection region 152, openings 154, and an open end 156. The
general direction flow of the heat exchange medium through the
exhaust manifold 150 is shown by the arrow A5.
Depending on the embodiment, the exhaust manifold 150 can be
mounted on the card 160, or positioned over or adjacent to the card
160. With the exhaust manifold 150 mounted on to the card 160, the
heat exchange system 100 and the card 160 are a single unit. This
makes installation, removal and servicing of the combined unit
easier and quicker, reducing the time and cost of maintenance and
repair.
The collection region 152 can direct the heat exchange medium to an
external device (not shown), such as a cooling system, a
refrigeration unit, a heat exchanger, a heater, pump, reservoir or
the like. The specific size and shape of the collection region 152
can vary and depending on factors including the flow rates, and the
properties of the heat exchange medium, i.e. pressure,
compressibility, viscosity, and the like. In some embodiments, such
as that shown, the collection region is significantly larger in
cross-section than the openings 154 and the opening of the open end
156.
The openings 154 are positioned along the exhaust manifold 150 and
function to allow flow to be directed from each of the exhaust
tubes 140 attached thereto into the collection region 152. While
shown being positioned along a common side of the exhaust manifold
150, in other embodiments the openings 154 can be on other sides,
or about the manifold 150. While the size and shape of the openings
154 can vary, to achieve an even flow through each of the openings,
the openings 154 typically have a common size and shape. The
particular size and shape of the openings 154 is dependent on the
particular application and can vary depending on factors including
the desired flow rate through the openings 154, and the properties
of the heat exchange medium, as noted above.
The exhaust manifold 150 also includes an open end 156. The open
end 156 has an opening 157 which allows the flow of heat exchange
medium from the manifold 150 to an external location (not shown).
The size and shape of the opening 157 can vary depending on the
embodiment, and on factors including the flow rate and the
properties of the heat exchange medium. The open end 156 can also
include a connector or exhaust connector 158, which functions to
attach the tube or hose to the external location to the exhaust
manifold 150. The connector 158 can include a valve, or valves, to
prevent or limit any leakage of the heat exchange medium. The
connector 158 can also be positioned away from the open end 156
along the tube to the external source. The connector 158 can be a
quick-disconnect connector to allow the external tube to be
relatively quickly disconnected from the exhaust manifold 150. Such
a quick-disconnect connector, in conjunction with the connector 118
on the intake manifold 110, facilitates the quick removal of the
card 160 from a test head, or any similar apparatus. This in turn
allows for reduced service time and less equipment down time. Also,
this provides more flexibility in allowing individual cards to be
serviced with impacting other cards in the equipment.
Depending on the embodiment of the present invention, the card 160
can be a channel card or a printed circuit board. The device 170
can be an electronic component, such as a multichip module, or MCM,
having pin electronics dies.
An example of a cooling apparatus or cooling plate is set forth in
U.S. Pat. No. 5,871,042, entitled LIQUID COOLING APPARATUS FOR USE
WITH ELECTRONIC EQUIPMENT, by Gutfeldt, et al., issued Feb. 16,
1999, which is hereby incorporated reference in its entirity.
FIG. 2 shows a top cut-away view of a portion of a heat exchange
system in accordance with at least one embodiment of the present
invention. A heat exchanger or cooling plate or cold plate 200
includes a structure 210, a inlet or intake connector 220 and a
outlet or exhaust connector 230. The general flow direction of a
heat transfer medium (not shown) shown by the arrows B1, B2, B3, B4
and B5. The cooling plate 200 can be removed from the rest of the
heat exchange system by the connectors 220 and 230 for repair,
maintenance or replacement of the cooling plate and/or the device
(not shown) that it is cooling.
In the embodiment shown, the structure 210 of the cooling plate 220
includes an external frame 211, a divider 212, channel 214, a lower
plate 216, an upper plate (not shown), an inlet 218 and an outlet
219.
The external frame 211 and the divider 212 form the channel 214,
which directs the coolant through the cooling plate 200, as shown
generally by arrows B2, B3 and B4. One example of how the flow can
be directed to selectively flow first over certain regions, which
are positioned above particular components of the device being
cooled, is shown in FIG. 2. A variety of other embodiments with
different internal flow patterns are possible by reshaping and
rearranging the frame 211, the divider 212 and the channel 214.
In the embodiment of the present invention shown in FIG. 2, the
divider 212 functions to direct the flow such that it first flows
over the regions X1 and X2 then on to region X3. The regions X1, X2
and X3 can show the positions of components, i.e. chips or dies, of
the device set below the cooling plate 200. In some embodiments,
the regions X1 and X2 locate pin electronics dies and the region X3
locates a digital ASIC chip. In these embodiments, since pin
electronics dies are typically more sensitive to temperature
levels, and variations thereof, than digital ASIC chips, the flow
of the coolant is directed first over the regions X1 and X2. In
certain embodiments, the pin electronics dies are most sensitive to
temperature effects along a specific edge of the die. By setting
this edge of the die as the leading edge, relative to the flow of
the heat transfer medium, the sensitivity of the die to heat can be
minimized.
As a result, with the embodiment of FIG. 2, uniform cooling can be
provided to the pin electronics dies in each of the devices, i.e.
MCMs, being cooled by each of the cooling plates 200 of a heat
exchange system.
Below the channel 214 is the lower plate 216 and above the channel
an upper plate (not shown in the cut-away of FIG. 2). The lower
plate 216 can be a heat transfer plate, which can be of a material
which allows a high rate of heat transfer, such as copper, brass,
aluminum and the like.
The structure 210 also includes the inlet 218 and the outlet 219
for allowing the flow into and out of the cooling plate 200.
Positioned upstream from the inlet 218 is the inlet connector 220
and positioned downstream from the outlet is the outlet connector
230. The connector 220 and 230 can also be positioned in contact
with, or part of, the structure 210. The connectors 220 and 230 can
include a valve, or valves, to prevent or limit any leakage of the
heat exchange medium. In some embodiments, the inlet connector 220
and the outlet connector 230 are quick-disconnect connectors to
facilitate the removal of the cooling plate 200 from the heat
exchange system. Using quick-disconnect connectors allows for a
reduction in the time need to remove the cooling plate 200,
reducing time need for servicing and equipment downtime. Usable
quick-disconnect connectors include as QD connectors available from
Eaton Aeroquip, Inc. located in Maumee, Ohio.
In certain embodiments of the present invention, the cooling plate
200 of FIG. 2, can be used as the heat exchanger 130 in the heat
exchange system 100 of FIG. 1.
FIG. 3 shows a side cross-sectional view of a portion of a heat
exchange system in accordance with at least one embodiment of the
present invention. The embodiment shown in FIG. 3 is an integrated
unit 300 that includes a heat exchanger 310, fasteners 320, a
backing or bolster plate 330, a card or device board 340 and a
device 350. Flow of a heat exchange medium is generally shown by
arrows C1 and C2.
With the heat exchanger 310, the device board 340 and the device
350 all secured together by the fasteners 320, the integrated unit
300 provides several functions. With the heat exchanger 310 and the
device 350 abutted, the transfer of heat therebetween is
facilitated. Since the heat exchanger 310 is secured over the
device 350, the heat exchanger 310 also functions as a lid for the
device 350, protecting its components. Also, with the fasteners 320
urging the heat exchanger 310 down against the device 350, the heat
exchanger 310 can function as a compression plate to secure the
device in the board 340. As a result, by using the heat exchanger
310 as not only a heat exchanger, but also a lid and a compression
plate, the integrated unit 300 eliminates the need for additional
components, reducing cost and complexity.
The heat exchanger 310 includes an outlet 312, a chamber 314, a
heat exchange plate 316, feet 317 and mounts 318. The heat
exchanger 310 is capable of transferring heat between the device
350 and the heat transfer medium (not shown) flowing through the
heat exchanger 310. The size and shape of the heat exchanger 310
can vary depending on the requirements of the particular
application. For example, the size of the heat exchanger 310 can be
directly dependent on the amount of heat that must be transferred
from the device 350 and the surface area available for the heat
transfer. As shown, the heat exchanger 310 is a cold plate.
The heat exchanger 310 can be of any of a variety of different
materials which allow heat transfer, including materials with high
heat transfer rates such as copper, brass, aluminum and the like.
The heat exchanger 310 can be a composition of different materials,
for instance, a material with high heat transfer properties can be
used at locations where heat transfer occurs, such as the heat
exchange plate 316, and a different material used for other
portions, such as an thermal insulating material at the external
areas. This composition of materials would allow greater heat
transfer and reduce potential for adverse effect such as
condensation.
The heat exchange medium flows through the heat exchanger, entering
at an inlet (not shown), passing through the chamber 314 and
exiting by an outlet 312. The chamber 314 can be formed to direct
the heat exchange medium within the heat exchanger 310. For
instance, the chamber 314 can be formed to direct the flow so that
it initially passes over the most heat producing and/or sensitive
components of the device 350. In some embodiments, the flow is
directed to pass over the pin electronic dies. The chamber 314 can
also include fins or similar structures to increase the surface
area and aid in heat transfer.
Positioned between the heat exchange medium in the chamber 314 and
the components of the device 350 is the heat exchange plate 316. To
facilitate heat transfer the heat exchange plate 316 can be formed
to be in direct contact with the components of the device 350.
Also, the heat transfer plate can be of a material having good heat
transfer characteristics, including, copper, brass, aluminum and
the like. The heat transfer plate can be placed away from the
device 350, as shown, by a set of feet 317, which can also act to
seal the space between the heat transfer plate and the device
350.
The heat exchanger 318 can also includes mounts or a set of plate
ears 318 for receiving the fasteners 320 and allowing the heat
exchanger to be secured to the rest of the unit 300.
The fasteners 320 are positioned between the heat exchanger 310 and
the bolster plate 330. The fasteners 320 function to urge the heat
exchanger 320 as a compression plate down against the device 350,
and the device 350 into the device board 340. Not only does this
compression aid in heat transfer between the heat exchanger and the
device 350, but as further detailed below, by pressing the device
350 into the device board 340, electrical contact between the
device 350 and the device board 340 can be facilitated. The
fasteners 320 can be compression bolts or similar articles.
The bolster plate 330 is positioned below the device board and
functions as compression plate.
In certain embodiments, the device board 340 is a printed circuit
board or a channel card. The device board 340 can function not only
to hold the unit 300, but it also can act supply electrical
connections to the device 350. As noted above, the device board can
also be used to mount intake and exhaust manifolds (not shown) for
the heat exchange system.
The device 350 includes a body 352, a frame 353, an interface 354,
a first component 356 and a second component 358. In certain
embodiments the body 352 is a multichip module or MCM, where one or
more chips or dies are mounted thereto. The frame 353 can function
to contain the interface 354, particularly where, described below,
a deformable material is used for the interface 354. In some
embodiments, the interface 354 is a conductive elastomer which
provides electrical connections between the device board 340 and
the body 352 including its components 356 and 358. One such
conductive elastomer is MPI available from Tyco, Inc. of
Attleborough, Mass. in a Kapton film available from Tyco, Inc. of
Attleborough, Mass.
In at least one embodiment of the present invention, as the MCM is
urged against the printed circuit board, by the actions of the heat
exchanger and the bolster plate as compression plates and the
compression bolts, the conductive elastomer is deformed and
electrical connections are formed between the MCM and printed
circuit board.
In other embodiments, the interface 354 can be a set of pins or
other leads extending either from the body 352 or the device board
340 to contact either the device board 340 or the body 352,
respectfully. Such pins or leads can be secured by conventional
means, such as by soldering.
Depending on the embodiment of the present invention, the first
component 356 can include one or more pin electronics dies. Since
in ATE applications pin electronics dies tend to be sensitive to
temperature levels and variations thereof, at least more than other
chips, such as digital ASIC chips, the pin electronics dies are
typically positioned furthest upstream, relative to other chips in
the MCM. That is, the pin electronics dies are positioned to be
cooled first by the coolant to assure that they are cooled by the
most uniform coolant. To aid in the heat transfer between the pin
electronics dies and the heat exchange plate 316 a thermal paste
357 can be applied therebetween. An example of a suitable thermal
paste is ATC 3.8, which is available from IBM, Inc. of East
Fishkill, N.Y.
In certain embodiments of the present invention, the second
component 358 can be a digital ASIC chip. As noted above, since
digital ASIC chips tend to be less temperature sensitive than pin
electronics dies, the digital ASIC chips can be positioned
downstream in the flow of the coolant from the pin electronics
dies.
In other embodiments of the present invention, the cooling plate
200 of FIG. 2 can be used as the heat exchanger 310 of the
integrated unit 300 of FIG. 3. Also, the integrated unit 300 can be
used in the heat exchange system 100 of FIG. 1.
FIG. 4a shows a top cut-away view of a cooling system in accordance
with at least one embodiment of the present invention. FIG. 4b
shows a side cut-away view of a portion of a heat exchange system
in accordance with at least one embodiment of the present
invention. The embodiment shown in FIGS. 4a and b is a cooling
system 400 that has a single manifold 405 mounted on the board 460,
for cooling a set of electronic devices 470. The combination
manifold 405 includes an intake manifold 410 and an exhaust
manifold 450, which are separated from each other by a flow
separating structure 407 positioned within the combination manifold
405. The separating structure 407 functions to divide the intake
manifold 410 from the exhaust manifold 450, so to not allow mixing
of the intake and exhaust flows of the heat transfer medium (not
shown).
Connected along the combination manifold 405 are a set of cooling
plates or cold plates 430 which in turn are positioned on the set
of devices 470. The manifold 405 and cooling plates 430 each have a
set of openings that are aligned to allow the heat transfer medium
to flow from the intake manifold 410 through the cooling plates 430
and out into the exhaust manifold 450. The flow of the heat
exchange medium is generally shown by the arrows D1, D2, D3, D4 and
D5 in FIG. 4a and E1, E2 and E3 in FIG. 4b.
The heat exchange medium can be any of a variety of substances
including a gas or a liquid. In some embodiments the heat exchange
medium is an inert liquid.
The separating structure 407 is shaped to direct the flow of the
heat exchange medium from the intake manifold 410 to the cooling
plate 430 and out of the cooling plate 430 into the exhaust
manifold 450. The separating structure 407 forms an intake passage
420 which directs flow from the intake manifold 410 to an opening
422, which abuts an opening 432 of the cooling plate 430, as shown
in FIG. 4b. In this manner the flow of the heat exchange medium
(not shown) can move from the intake manifold 410 into the intake
passage, as shown generally by arrow E1, then through the openings
422 and 432 into a chamber 434, as shown generally by arrow E2, and
then over a heat transfer plate 436, as shown generally by the
arrow E3. Since FIG. 4b is a cross-section, as defined in FIG. 4a,
the return path and exit of the flow are not shown in FIG. 4b.
With the openings 422 and 432 positioned adjacent each other, a
variety of different means and structures can be use to form a seal
between the openings 422 and 432. In at least one embodiment an
O-ring, positioned between the combination manifold and the cooling
plate 430, is used. Also, a quick-disconnect connector can be used
between the openings 422 and 432. Such a connector can include a
valve, or valves, to prevent or limit any leakage of the heat
exchange medium.
In certain embodiments, the cooling plate 430 can be removed from
both the combination manifold 405 and the device 470 to allow for
access to the device 470 for servicing, repair or replacement. In
some embodiments, the cooling plate 430 is secured to the board 460
such that it is capable of also functioning as a lid for the device
470 and/or a compression plate. Some of these embodiments are
described above in reference to FIG. 3.
The present invention can also be used to supply a heat exchange
medium to more than one card or board by using an intake manifold
and an exhaust manifold positioned at least adjacent to the set of
cards, with intake and exhaust tubes connecting the manifolds to
the cards. In turn, the cards can each have intake and exhaust
manifolds for supplying the heat exchangers mounted thereto. This
dual parallel heat exchange system provides not only consistent and
predictable cooling to each of the components on a given card, but
also to each of the cards in a set of cards.
While the present invention can be used in a variety of ATE
applications, the invention is also capable of being used in many
other non-ATE applications as well. In at least some embodiments,
the invention can be employed in applications such as servers,
where, for example, 1U size boards, i.e. 1.75'' tall, have
typically at least 2.times. processors and preferably 4.times.. The
invention's cooling and fluid distribution allows desired
modularity and flexibility in serving individual processors of such
applications.
Having described this invention in connection with a number of
embodiments, modification will now certainly suggest itself to
those skilled in the art. As such, the invention is not to be
limited to the disclosed embodiments except as required by the
appended claims.
* * * * *